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161.
AbstractObjective: Particular testing by functional decomposition of the automated driving function can potentially contribute to reducing the effort of validating highly automated driving functions. In this study, the required size of test suites for scenario-based testing and the potential to reduce it by functional decomposition are quantified for the first time.Methods: The required size of test suites for scenario-based approval of a so-called Autobahn-Chauffeur (SAE Level 3) is analyzed for an exemplary set of scenarios. Based on studies of data from failure analyses in other domains, the possible range for the required test coverage is narrowed down and suitable discretization steps, as well as ranges for the influence parameters, are assumed. Based on those assumptions, the size of the test suites for testing the complete system is quantified. The effects that lead to a reduction in the parameter space for particular testing of the decomposed driving function are analyzed and the potential to reduce the validation effort is estimated by comparing the resulting test suite sizes for both methods.Results: The combination of all effects leads to a reduction in the test suites’ size by a factor between 20 and 130, depending on the required test coverage. This means that the size of the required test suite can be reduced by 95–99% by particular testing compared to scenario-based testing of the complete system.Conclusions: The reduction potential is a valuable contribution to overcome the parameter space explosion during the validation of highly automated driving. However, this study is based on assumptions and only a small set of exemplary scenarios. Thus, the findings have to be validated in further studies. 相似文献
162.
Limit values (LVs) are legal concentration limits for constituents, residues and contaminants in consumer products or for
emissions from production processes into environmental compartments. They are a traditional regulatory aid to manage chemicals
in human environments. To make them proactive, LVs should become enforced by means of a transparent and informed decision
process whose starting point is the Basic Rule of Environmental Hygiene, BREH:Avoid useless exposure as far as possible, minimize useful exposure in a reasonable manner, and prevent that exposure which
is dangerous. The BREH calls upon minimizing exposure not only according toon site risk potentials and acceptance, but also tooff site avoidability and acceptability. 相似文献
163.
Corinna Nunneri Hermann J. Lenhart Benjamin Burkhard Wilhelm Windhorst 《Regional Environmental Change》2008,8(1):31-43
Offshore wind power generation represents a chance to supply energy in a more sustainable way; however, the ecological risks
associated with the construction and operation of offshore wind farms are still largely unknown. This paper uses the concept
of ecological risk for analysing ecological changes during construction of offshore wind farms. “Ecological risk” is defined
as the potentially reduced ability of providing ecosystem services. The ERSEM ecosystem model allows assessing ecological
risk based on a number of selected variables (integrity indicators) and under the assumption that increased suspended matter
concentration during construction of wind farms affects ecosystem functioning. We conclude that ecological risk is adequate
to describe the effects of wind farm constructions, although the computation procedure still needs to be refined and the choice
of indicators further optimised. In this context, the choice of indicators available in modelling as well as in monitoring
time-series may offer the way forward. 相似文献
164.
Sheng Fulai Gary Flomenhoft Timothy J. Downs MaÁngeles Grande‐Ortiz Dana Graef Bert Scholtens Arthur P.J. Mol David A. Sonnenfeld Gert Spaargaren Rajeev K. Goel Edward W.T. Hsieh Serban Scrieciu Reinhard Steurer Christine Polzin Genia Kostka Tiho Ancev Elke Pirgmaier Frank Boons Karl‐Henrik Robèrt Christopher Bryant Ke Zhou Surya Raj Acharya David Huberman Denis J. Sonwa Michelle Mycoo Dabo Guan Klaus Hubacek U. Rashid Sumaila Hector G. Lopez‐Ruiz G. Jason Jolley Michael L. Dougherty André Francisco Pilon Ravi Prakash Tulus Tambunan Sebastian Hermann 《Natural resources forum》2011,35(1):63-72
165.
Klemens Marx Johannes Bolhàr-Nordenkampf Tobias Pröll Hermann Hofbauer 《International Journal of Greenhouse Gas Control》2011,5(5):1199-1205
A semi-commercial 10 MWth chemical looping combustion (CLC) plant for power production is proposed as a next scale demonstration plant after successful operation of a 120 kW CLC pilot rig. The design criteria for the CLC boiler are derived from the experience obtained from the CLC pilot rig at Vienna University of Technology. The IPSEpro simulation environment is chosen for implementation of the process flow sheet of the CLC power plant. A single pressure steam cycle is suggested for this small scale demonstration plant. Heat exchangers and a five-stage steam turbine are arranged. Basic design parameters of the power plant are derived from detailed mass and energy investigations and discussed. It turns out that the net electric efficiency of such a small scale plant can be expected to be in the range of 32.5–35.8%. However, a demonstration of CLC at such a scale is necessary in order to gain confidence in more sophisticated CLC power generation concepts at larger scale. 相似文献
166.
Scenarios of global bioenergy production: The trade-offs between agricultural expansion, intensification and trade 总被引:1,自引:0,他引:1
Hermann Lotze-Campen Alexander Popp Tim Beringer Christoph Müller Alberte Bondeau Stefanie Rost Wolfgang Lucht 《Ecological modelling》2010,221(18):2188-2196
Increased future demands for food, fibre and fuels from biomass can only be met if the available land and water resources on a global scale are used and managed as efficiently as possible. The main routes for making the global agricultural system more productive are through intensification and technological change on currently used agricultural land, land expansion into currently non-agricultural areas, and international trade in agricultural commodities and processed goods. In order to analyse the trade-offs and synergies between these options, we present a global bio-economic modelling approach with a special focus on spatially explicit land and water constraints as well as technological change in agricultural production. For a global bioenergy demand scenario reaching 100 ExaJoule (EJ) until 2055 we derive a required rate of productivity increase on agricultural land between 1.2 and 1.4 percent per year under different land allocation options. A very high pressure for yield increase occurs in Sub-Saharan Africa and the Middle East, even without additional bioenergy demand. Moreover, we analyse the implicit values (shadow prices) of limited water resources. The shadow prices for bioenergy are provided as a metric for assessing the trade-offs between different land allocation options and as a link between the agricultural and energy sector. 相似文献
167.
Daniel Aguilera-Olivares Camila Burgos-Lefimil Wara Melendez Luis Flores-Prado Hermann M. Niemeyer 《Chemoecology》2016,26(5):163-172
Nestmate recognition is a necessary capacity for the occurrence of discrimination between nestmate and non-nestmate individuals. In one-piece nesting termites, which nest and forage in a single piece of wood, nestmate recognition is poorly studied mainly because the probability of encountering exogenous individuals is low in comparison with separate-piece nesting termites. Previous work described that production of soldiers of Neotermes chilensis, a one-piece nesting termite, increased when the risk of invasion of their colony increased, for example when neighboring colonies were present in the same nesting substrate and members of different colonies met when digging galleries. If soldiers are to fulfill their defensive role under these circumstances, they should show nestmate recognition ability; moreover, based on work on other social insects, such nestmate recognition should be based on cuticular compounds (CC). Bioassays were performed in which a soldier of N. chilensis was confronted with a nestmate or non-nestmate primary reproductive, pseudergate or another soldier, and in which a soldier was confronted with untreated and with CC-deprived dead primary reproductives. The results showed that soldiers were indeed more aggressive toward non-nestmates than nestmates for all castes, and that this discrimination was mediated mainly by qualitative (simple matching coefficient) and quantitative (Renkonen index) differences in CC. 相似文献
168.
169.
170.
Hermann A. Kahle 《Die Naturwissenschaften》1957,44(22):573-578